Question

if csc theta = -2 find cos theta

Answer 1

Answer:

cosec θ = -2

1 / sin θ = -2            since cosec θ = 1/ sin θ

sin θ = -1/2

sin θ = - sin ( π / 6 )

sin θ = sin ( - π /6 )                 since sin ( -θ) = - sin (θ)

so   θ = -π / 6

now cos θ = cos ( -π /6)

cos θ = cos ( π/6)               since cos (-θ) = cos (θ)

so  cos θ = $\frac{\sqrt 3}{2}$

hope it helps !